Mentzelia obscura
Pacific blazing star
Family: Loasaceae · Type: Herb · Native
Mentzelia obscura (Pacific blazing star) is a native California herb in the Loasaceae family, recognized by pale unmottled seeds and strongly curved fruits.
Pacific blazing star is a California native annual found in the Mojave Desert bioregion in sandy to rocky washes, creosote-bush scrub, and Joshua-tree woodland at elevations of 200 to 1,600 meters. Flowering from February to March, this plant produces bright yellow flowers 3 to 7 millimeters long with an orange to yellow base. Growing with erect to decumbent stems 8 to 45 centimeters tall, it has variable green leaves ranging from 1 to 22 centimeters long and can be entire or lobed. Its leaves vary widely in shape, sometimes entire and sometimes deeply lobed, creating a distinctive appearance across different plants. The fruit is curved less than 250 degrees, 11 to 31 millimeters long, with tan seeds approximately 1 millimeter in size.
Identification and appearance
Key characters: 18 sympatric species; pale unmottled seeds and strongly curved fruits
Habitat and range
Habitat: Sandy to rocky washes, slopes, roadsides, creosote-bush scrub, blackbush scrub, Joshua-tree woodland
Elevation: 200-1616 m
California counties: San Bernardino, Inyo, Riverside, Kern, Los Angeles, San Diego, Tulare
Outside California: to Utah, Arizona, northern Mexico
Bloom period
Mentzelia obscura blooms Feb-Mar.
How to tell it apart
vs Camissoniopsis: Mentzelia has many stamens and 3 stigmas; Camissoniopsis has 8 stamens and 4 stigmas.; vs Leptosiphon: Mentzelia has free petals and many stamens; Leptosiphon has fused petals forming a tube.; vs Emmenanthe: Mentzelia has free petals and 3 stigmas; Emmenanthe has fused bell-shaped petals.; vs Eschscholzia: Mentzelia has many stamens and 3 stigmas; Eschscholzia has many stamens and 4 stigmas.; vs Potentilla: Mentzelia has 3 stigmas and capsule fruit; Potentilla has many pistils and achene fruits.
Frequently asked questions
Is Mentzelia obscura native to California?
Yes. Mentzelia obscura is native to California (recorded as native).
When does Mentzelia obscura bloom?
Mentzelia obscura blooms Feb-Mar.
Where in California does Mentzelia obscura grow?
Mentzelia obscura occurs in San Bernardino, Inyo, Riverside, Kern, Los Angeles, San Diego, Tulare, at elevations of 200-1616 m.
What plant family does Mentzelia obscura belong to?
Mentzelia obscura is in the Loasaceae family, genus Mentzelia.
What habitat does Mentzelia obscura grow in?
Mentzelia obscura grows in Sandy to rocky washes, slopes, roadsides, creosote-bush scrub, blackbush scrub, Joshua-tree woodland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.